The invention relates to a power semiconductor component, having a low on resistance.
One important aim in the development of power semiconductor components is to produce components which have the highest possible blocking capability and which nevertheless have a low on resistance and which simultaneously have the lowest possible switching losses.
One possibility for reducing the on resistance of a power semiconductor component for a given blocking capability is to use the compensation principle, described for example in U.S. Pat. No. 4,754,310 (Coe), U.S. Pat. No. 5,216,275 A1 (Chen), U.S. Pat. No. 5,438,215 or DE 43 09 764 C2 (Tihanyi).
A further possibility for reducing the on resistance of a semiconductor component is to provide a field electrode insulated dielectrically from the drift region. Components of this type are described in U.S. Pat. No. 4,903,189 (Ngo), U.S. Pat. No. 4,941,026 (Temple), U.S. Pat. No. 6,555,873 B2 (Disney), U.S. Pat. No. 6,717,230 B2 (Kocon) or U.S. Pat. No. 6,853,033 B2 (Liang).
EP 1 073 123 A2 (Yasuhara) describes a lateral power MOSFET having a plurality of auxiliary electrodes which are arranged in a drift region of the component and which are insulated from the drift region by a dielectric. The auxiliary electrodes are composed of a semi-insulating polysilicon (SIPOS) or a resistive material and are connected between a source connection and a drain connection of the component. The auxiliary electrodes bring about the formation of a depletion zone (depletion layer) in the drift region when the component is driven in the off state.
GB 2 089 118 A describes a power MOSFET having a resistive layer which extends along the drift region between a gate electrode and a drain electrode and which “spreads” an electric field in the drift region with the aim of increasing the dielectric strength.
U.S. Pat. No. 5,844,272 (Söderbärg) describes a lateral high-frequency transistor with a drift region running in the lateral direction of a semiconductor body.
US 2003/0073287 A1 (Kocon) proposes providing a plurality of field electrodes along the drift path of a semiconductor component, the field electrodes being at different potentials.